Preheat the oven to 400F. Cut potatoes in half and poke them with the tinges of a fork. Wrap them in aluminum foil and bake on an ungreased cookie sheet for about 1 hour until soft. Remove and set aside to cool at least 5 minutes.

When the potatoes are cool enough to handle, scoop the filling into a large bowl. With a hand masher or electric mixer, beat potatoes, alternating with the milk and butter until the mixture resembles a smooth puree. Beat in the honey, mustard, and salt. Serve immediately.